ES2928826T3 - Enhanced High Gloss Recycling Composition - Google Patents

Abstract

A polyolefin composition (C) that can be obtained by blending: a recycled blend (A) with a virgin polypropylene homopolymer and, optionally, a virgin high-density polyethylene. (Automatic translation with Google Translate, without legal value)

Description

DESCRIPTION

Enhanced High Gloss Recycling Composition

field of invention

The present invention relates to improved recycling compositions having high gloss and to the use of virgin polypropylene and virgin polyethylene to improve gloss.

Background

Gloss has been mainly evaluated in the field of polypropylene heterophasic compositions. However, gloss is also an issue when it comes to recycling polyolefin materials. Generally speaking, the brightness observed for various recycling streams rules out their relevant industrial application. Surprisingly, this observation is even more true for the highest quality recycling materials available on the market. Therefore, there is a great demand for compositions having a considerable amount of recycled material and at the same time acceptable mechanical properties as well as good gloss. Document WO2019086359, for example, refers to compositions comprising recycled polypropylene, however, it does not mention the problem of improving gloss.

So far very few works are known. For example, KIM, Soon-Deok, et al. "Effect of Ethylene-Propylene Copolymer Composition on Morphology and Surface Properties of Impact Poly (propylene) Copolymer" In: Macromolecular Symposia. Weinheim: WILEY-VCH Verlag, 2012. S. 27-33 have evaluated the influence of EPR composition in heterophasic PP (Samsung Total Petrochemicals) on gloss. In the field of material recycling, practically nothing is known when it comes to brightness.

Therefore, there remains a need to improve such recycling streams to address the aforementioned needs.

Summary of the invention

In its broadest aspect, the present invention insofar as it provides

HLZ:SC

a polypropylene composition (C) that can be obtained by combining:

a) from 20.0 to 80.0% by weight, based on the total weight of the composition, of a combination (A) comprising

A-1) isotactic polypropylene

A-2) polyethylene and copolymers containing ethylene

wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:7,

Y

wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste;

b) from 20.0 to 80.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having

(i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min

(ii) a flexural modulus (ISO 178) of at least 1200 MPa

c) from 0.0 to 15.0% by weight of a virgin high-density polyethylene having

(i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 2 to 8 g/10 min

(ii) a density of 950 to 960 kg/m3 (ISO 1183),

d) 0.0 to 5.0% by weight of a masterbatch of polypropylene and carbon black

e) from 0.0 to 3.0% by weight of additives selected from antioxidants and/or UV stabilizers, such that components a) to e) add up to 100% by weight.

In a first aspect, the present invention provides

a polypropylene composition (C) that can be obtained by combining:

a) from 20.0 to 50.0% by weight, based on the total weight of the composition, of a combination (A) comprising A-1) isotactic polypropylene

A-2) polyethylene and copolymers containing ethylene

wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:7, preferably from 19:1 to 3:2, and wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste;

b) from 50.0 to 80.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having

(i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min

(ii) a flexural modulus (ISO 178) of at least 1200 MPa

c) from 0.0 to 15.0% by weight of a virgin high-density polyethylene having

(i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 2 to 8 g/10 min

(ii) a density of 950 to 960 kg/m3 (ISO 1183),

d) 0.0 to 5.0% by weight of a masterbatch of polypropylene and carbon black

e) from 0.0 to 3.0% by weight of additives selected from the group of antioxidants and/or UV stabilizers

so that components a) to e) add up to 100% by weight.

In a second aspect, the present invention provides

a polypropylene composition (C) that can be obtained by combining:

a) from 50.0 to 80.0% by weight, based on the total weight of the composition, of a combination (A) comprising

A-1) isotactic polypropylene

A-2) polyethylene and copolymers containing ethylene

wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 3:2 to 2:3,

Y

wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste;

b) from 20.0 to 50.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having

(iii) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min

(iv) a flexural modulus (ISO 178) of at least 1200 MPa

c) from 0.0 to 5.0% by weight of a masterbatch of polypropylene and carbon black

d) from 0.0 to 3.0% by weight of additives selected from antioxidants and/or UV stabilizers such that components a) to d) add up to 100% by weight.

The present invention also relates to the use of a virgin polypropylene homopolymer together with a virgin high-density polyethylene in a composition comprising a combination (A),

so that combination (A) comprises

A-1) isotactic polypropylene

A-2) polyethylene and copolymers containing ethylene

wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:2, and

wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste;

such that combination (A) is present in an amount of 20.0 to 35.0% by weight, based on the total weight of the composition;

so that said virgin polypropylene homopolymer has

(i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min

(ii) a flexural modulus (ISO 178) of at least 1200 MPa

and is present in an amount of 50.0 to 75.0% by weight, based on the total weight of the composition, and so that said high density virgin polyethylene has

(i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 2 to 8 g/10 min

(ii) a density of 950 to 960 kg/m3 (ISO 1183)

and is present in an amount of 5 to 15% by weight, based on the total weight of the composition, to increase the gloss (GU; 60°, measured as described in the experimental part) by at least 2% of the value of the measurement against the gloss of the composition that does not contain the virgin polypropylene homopolymer and that does not contain the virgin high density polyethylene.

Unless otherwise defined, all technical and scientific terms used in this document have the same meaning as that normally understood by a person skilled in the art to which the invention pertains. However, any methods and materials similar or equivalent to those described herein may be used in practice for the assays of the present invention, preferred materials and methods are described herein. In describing and claiming the present invention, the following terminology will be used in accordance with the definitions set forth below.

Gloss means gloss measured at an angle of 60° unless otherwise indicated.

Unless clearly indicated otherwise, use of the terms "a", "an", and the like refers to one or more.

For the purposes of this description and subsequent claims, the term "recycled waste" is used to indicate a material recovered from both post-consumer waste and post-industrial waste, as opposed to virgin polymers. Post-consumer waste refers to objects that have completed at least a first cycle of use (or life cycle), that is, they have already fulfilled their first purpose; while post-industrial waste refers to manufacturing scrap, which normally does not reach the consumer. The limonene content makes it possible to find out if a material can be classified as "recycled waste" or not. In addition to other contaminants such as the presence of fatty acids, polystyrene, polyamide, paper, wood and the like can be used to determine whether or not a material is "recycled waste".

The term "virgin" denotes newly produced materials and/or objects before their first use, which have not yet been recycled. Such virgin material does not contain limonene, ie detectable values are significantly below 0.10 ppm when measured as described in the experimental part.

Many different types of polyethylene or polypropylene can be present in "recycled waste". Combination (A) according to the present invention includes at least one polypropylene, polyethylene, limonene.

Combination (A) is further characterized by an istotactic polypropylene content. The isotactic polypropylene content can be easily determined as described in the experimental part.

Combination (A) is further characterized by a content of polyethylene and ethylene-containing copolymers, so that again the determination is easily possible by means of a calibration method as described in the experimental part. Polyethylene denotes any of the conventional polyethylenes such as LDPE, LLDPE, MDPE and HDPE.

Ethylene-containing copolymers are widespread and can include, for example, ethylene propylene copolymers such as ethylene propylene rubber, plastomers such as C2C8 resins, and innumerable other polymers, including units derived from ethylene.

The expression "recycled material", as used herein, indicates materials reprocessed from "recycled waste".

A polymer blend denotes a mixture of two or more polymeric components. In general, the blend can be prepared by mixing the two or more polymer components. Suitable mixing procedures known in the art are post-polymerization mixing procedures. Post-polymerization blends can be dry blends of polymer components such as polymer powders and/or composite polymer granules or melt blends by melt blending the polymer components.

Unless otherwise indicated, "%" refers to % by weight.

As a matter of definition, a virgin polypropylene homopolymer as well as a virgin polyethylene can also contain a polymeric nucleating agent.

Preferably, the polypropylene composition (C) according to the present invention includes a virgin polypropylene homopolymer having a tensile strength of 30 to 45 MPa (ISO 527-2), preferably a tensile strength from 31 to 37 MPa.

Simultaneously, but independently therefrom, the heat deflection temperature B (0.45 MPa; ISO 75-2) of the virgin polypropylene homopolymer is at least 76°C, preferably up to 120°C. In another aspect, the virgin high density polyethylene preferably has a tensile modulus (1 mm/min; ISO 527-2) of at least 800 MPa, more preferably at least 850 MPa. Generally, the tensile modulus will not exceed 1350 MPa.

In a still further aspect, the virgin high density polyethylene preferably has a heat deflection temperature (0.45 MPa; ISO 75-2) of at least 62°C, more preferably at least 63°C. Generally, the heat deflection temperature will not exceed 100°C.

In a still further aspect, the virgin high density polyethylene preferably has a Shore D hardness of 56 to 64 (ISO 868), preferably 58 to 64.

The preferred tensile strength, preferred heat deflection temperature, preferred tensile modulus, and preferred heat deflection temperature may be present individually or in combination.

In general, the composition (C) according to the present invention will be black in color. This is affected by the incorporation of a masterbatch of polypropylene and carbon black as known in the art. In general, the amount of masterbatch of polypropylene and carbon black will not be more than 5% by weight, preferably not more than 4% by weight and most preferably not more than 2.5% by weight. The masterbatch of polypropylene and carbon black is a dispersion of carbon black in an amount of 35 to 45% by weight in polypropylene, preferably approximately 40% by weight in polypropylene. Typically, the polypropylene used for the carbon black dispersion will be a virgin polypropylene.

The preparation of the composition (C) according to the present invention is simple. Virgin polypropylene homopolymers and virgin high density polyethylenes suitable for this purpose are commercially available.

Detailed description

According to a first embodiment of the present invention, the combination (A) has a limonene content determined using solid phase microextraction (HS-SPME-GC-MS) from 0.1 ppm to 100 ppm, preferably from 1 ppm to 50 ppm, more preferably 2 ppm to 50 ppm, most preferably 3 ppm to 35 ppm. In a second embodiment, combination (A) has a limonene content determined using solid phase microextraction (HS-SPME-GC-MS) from 0.10 ppm to less than 1 ppm, preferably from 0.10 to less than 0. 0.85 ppm, most preferably from 0.10 to less than 0.60 ppm.

The combination (A) according to the second embodiment can be prepared by subjecting the combination (A) according to the first embodiment to washing and/or aeration. Laundering can be done by industrial washing machines such as those provided by Herbold Meckesheim GmbH. Depending on the origin of the waste stream, multiple wash cycles may be required. Various aeration processes such as those described in US 5,767,230 are also known in the art. US 5,767,230 is incorporated herein by reference. The process as described in US 5,767,230 is preferably combined with a washing step as described above.

A particularly preferred embodiment is

a polypropylene composition (C) that can be obtained by combining:

a) from 20.0 to 40.0% by weight, based on the total weight of the composition, of a combination (A) comprising

A-1) isotactic polypropylene

A-2) polyethylene and copolymers containing ethylene

wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:2,

Y

wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste;

b) from 60.0 to 80.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having

(v) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min

(vi) a flexural modulus (ISO 178) of at least 1200 MPa

c) from 0.0 to 5.0 % by weight of a masterbatch of polypropylene and carbon black

d) from 0.0 to 3.0% by weight of additives selected from antioxidants and/or UV stabilizers such that components a) to d) add up to 100% by weight.

In this embodiment no virgin polyethylene is added. In other words, the composition does not include virgin polyethylene. In this embodiment, the masterbatch of polypropylene and carbon black is preferably present in an amount of 1.0 to 3.0% by weight. The invention insofar as it provides as a particularly preferred embodiment

a polypropylene composition (C) that can be obtained by combining:

a) from 20.0 to 32.0% by weight, based on the total weight of the composition, of a combination (A) comprising A-1) isotactic polypropylene

A-2) polyethylene and copolymers containing ethylene

wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:2,

Y

wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste;

b) from 65.0 to 79.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having

(vii) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min

(viii) a flexural modulus (ISO 178) of at least 1200 MPa

c) 1.0 to 3.0% by weight of a masterbatch of polypropylene and carbon black

d) from 0.0 to 3.0% by weight of antioxidants and/or UV stabilizers

so that components a) to d) add up to 100% by weight.

An alternative embodiment also preferred is

a polypropylene composition (C) that can be obtained by combining:

a) from 20.0 to 35.0% by weight, based on the total weight of the composition, of a combination (A) comprising A-1) isotactic polypropylene

A-2) polyethylene and copolymers containing ethylene

wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:2, and

wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste;

b) from 50.0 to 74.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having

(i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min

(ii) a flexural modulus (ISO 178) of at least 1200 MPa

c) from 5.0 to 15.0% by weight of a virgin high-density polyethylene having

(iii) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 2 to 8 g/10 min

(iv) a density of 950 to 960 kg/m3 (ISO 1183),

d) 1.0 to 3.0% by weight of a masterbatch of polypropylene and carbon black

e) from 0.0 to 3.0% by weight of additives selected from the group of antioxidants and/or UV stabilizers such that components a) to e) add up to 100% by weight.

These specifically preferred embodiments can be combined with all aspects described herein and the claims with respect to virgin polypropylene, virgin polyethylene and/or masterbatch of polypropylene and carbon black.

experimental part

measurement methods

Flow index

The melt flow rate (MFR) is determined according to ISO 1133 and is indicated in g/10 min. The MFR is an indication of the fluidity and therefore the processability of the polymer. The higher the melt index, the lower the viscosity of the polymer. The MFR2 of polypropylene is determined at a temperature of 230 °C and a load of 2.16 kg. The MFR2 of polyethylene is determined at a temperature of 190 °C and a load of 2.16 kg. Quantity of iPP, polystyrene, polyethylene (and ethylene-containing copolymers), polyethylene terephthalate, and quantity of polyamide-6

To establish different calibration curves, different standards were combined, iPP and HDPE and iPP, PS and PA6. For quantification of foreign polymer content, IR spectra were recorded in solid state using a Bruker Vertex 70 FTIR spectrometer. The films were prepared with a compression molder at 190°C with a clamping force of 4-6 MPa. The thickness of the films for the calibration standards for iPP and HDPE was 300 pm and for the quantification of iPP, PS and PA 6 a film thickness of 50-100 pm was used. Normal transmission FTIR spectroscopy is employed using a 4000-400 cm-1 spectral range, 6 mm aperture, 2 cm-1 spectral resolution, 16 background scans, 16 spectrum scans, zero fill factor. interferogram of 32 and a strong Norton Beer apodization.

The absorption of the band at 1167 cm -1 in iPP is measured and the iPP content is quantified according to a calibration curve (absorption/thickness in cm vs. iPP content in wt%).

The absorption of the strip is measured at 1601 cm-1 (PS) and 3300 cm-1 (PA6) and the content of PS and PA6 is quantified according to the calibration curve (absorption/thickness in cm vs. PS content). and PA in % by weight). The content of polyethylene and ethylene-containing copolymers is obtained by subtracting (iPP+PS+PA6) from 100, taking into account the content of non-polymeric impurities as determined in the following methods. The analysis is performed as a double determination.

amount of talc and chalk

Talc and chalk contents were measured by thermogravimetric analysis (TGA); experiments were performed with a Perkin Elmer TGA 8000. Approximately 10-20 mg of material was placed in a platinum tray. The temperature was equilibrated at 50 °C for 10 minutes, then increased to 950 °C under nitrogen at a heating rate of 20 °C/min. Weight loss between approx. 550 °C and 700 °C (WCO2) was assigned to the CO2 evolved from the CaCO3, and therefore the chalk content was evaluated as:

Chalk content = 100/44 x WCO2

Subsequently, the temperature was reduced to 300 °C at a cooling rate of 20 °C/min. The gas was then changed to oxygen and the temperature was raised to 900 °C again. The weight loss at this stage was assigned to carbon black (Wcb). Knowing the carbon black and chalk content, the ash content excluding chalk and carbon black was calculated as:

Ash content = (Ash residue) - 56/44 x WCO2 - Wcb Where the ash residue is the % by weight measured at 900 °C in the first stage carried out in the presence of nitrogen. The ash content is estimated to be the same as the talc content for the investigated recyclates.

amount of paper and wood

Paper and wood contents were determined by conventional laboratory methods including milling, flotation, microscopy, and thermogravimetric analysis (TGA).

amount of metals

The metal content was determined by X-ray fluorescence (XRF).

amount of limonene

The limonene content was determined by solid phase microextraction (HS-SPME-GC-MS).

Additional details regarding the specific sample are provided below.

Amount of total fatty acids

The fatty acid content was determined by solid phase microextraction (HS-SPME-GC-MS). Additional details regarding the specific sample are provided below.

Tensile moduli (TM) (and tensile strength) were measured according to ISO 527-2 (crosshead speed = 1 mm/min for modulus determination, then changing to 50 mm/min until break at 23 °C) using injection molded test pieces as described in EN ISO 5247-2 (dog bone shape, 4 mm thick). The measurement was carried out after 96 h of conditioning time of the specimen under conventional climatic conditions (23 °C and 50 % relative humidity).

The impact force was determined as the Charpy Notched Impact Strength (NIS) according to ISO 179-1 eA at 23 °C on 80 x 10 x 4 mm injection molded test pieces prepared according to EN ISO 1873-2. According to this standard, samples are analyzed after 96 hours of conditioning at 23°C and 50% relative humidity.

The gloss was measured according to DIN 67530 at an angle of 60° on injection-moulded granular test pieces. Additional measurements were made at 85°. Unless otherwise stated, "gloss" indicates the gloss measured according to DIN 67530 at an angle of 60°.

The modulus of flexure was determined by bending at 3 points in accordance with ISO 178 on 80 x 10 x 4 mm injection molded specimens prepared in accordance with ISO 294-1:1996.

The density was measured according to ISO D 1183-187. Sample preparation is done by compression molding according to ISO 1872-2:2007.

The heat deflection temperature was determined according to ISO 75-2.

The HDT was determined on 80x10x4 mm3 injection molded test specimens prepared in accordance with ISO 1873-2 and stored at 23 °C for at least 96 hours prior to measurement. The test was carried out on flat-supported specimens in accordance with ISO 75, condition A, with a nominal surface tension of 1.80 MPa.

Shore D hardness was determined according to ISO 868.

examples

As mixture (A) a recycled rich in polypropylene and a lower quality polypropylene/polyethylene copolymer that contains recycled, both recycled from domestic waste, have been used as mixture (A).

Recycled rich in polypropylene

Isotactic polypropylene 92% by weight

Polyethylene and polyethylene copolymers 7% by weight

Ratio iPP/(PE+PE-CoPo) 13:1

Polystyrene << 1.0% by weight

Polyamide-6 < 0.3% by weight

Poly(ethylene terephthalate) traces

Talc content < 0.5% by weight

Chalk content < 0.5% by weight

Limonene content 2.1 ppm

Total fatty acid content na

Limonene content

Measurement

Limonene quantification was performed using solid phase microextraction (HS-SPME-GC-MS) by addition of standards.

50 mg of ground samples were weighed into 20 mL headspace vials and after adding limonene at different concentrations and a glass lined magnetic stir bar, the vial was closed with a silicone/PTFE lined magnetic cap. Microcapillaries (10 pl) were used to add dilute limonene standards of known concentrations to the sample. The addition of 0, 2, 20 and 100 ng is equivalent to 0 mg/kg, 0.1 mg/kg, 1 mg/kg and 5 mg/kg of limonene, in addition, standard amounts of 6.6, 11 and 16.5 mg/kg of limonene in combination with some of the samples analyzed in this application. For quantification, 93-ion acquired in mode was used. SIM. The enrichment of the volatile fraction was carried out by headspace solid phase microextraction with a Stableflex 50/30 pm 2 cm fiber coated with DVB/Carboxene/PDMS at 60 °C for 20 minutes. Desorption was carried out directly in the heated injection port of a GCMS system at 270 °C. GCMS Parameter:

Column: 30m HP 5MS 0.25*0.25

Injector: Splitless with 0.75mm SPME liner, 270°C

Temperature program: -10 °C (1 min)

Carrier gas: Helium 5.0, linear velocity 31 cm/s, constant flow

MS: Single Quadrupole, Direct Interface, 280 °C Interface Temperature

Acquisition: SIM scan mode

Scan Parameter: 20-300 amu

SIM parameter: m/Z 93, dwell time 100 ms

Table 2: Limonene content

Total free fatty acid content

Quantification of fatty acids was carried out by headspace solid phase microextraction (HS-SPME-GC-MS) by addition of standards.

Ground 50 mg samples were weighed into a 20 mL headspace vial and, after adding limonene at different concentrations and a glass lined magnetic stir bar, the vial was closed with a silicone/PTFE lined magnetic cap. 10 µl microcapillaries were used to add a dilute mixture of free fatty acids (acetic acid, propionic acid, butyric acid, pentanoic acid, hexanoic acid and octanoic acid) of known concentrations to the sample at three different levels. The addition of 0, 50, 100, and 500 ng equals 0 mg/kg, 1 mg/kg, 2 mg/kg, and 10 mg/kg of each individual acid. For quantification, ion 60 acquired in SIM mode was used for all acids except propanoic acid, using ion 74 in this case.

GCMS Parameter:

Column: 20 m ZB Cera plus 0.25*0.25

Inlet: 5:1 split glass lined split liner, 250°C

Temperature program: 40 °C (1 min) at 6 °C/min at 120 °C, 15 °C at 245 °C (5 minutes)

Carrier: Helium 5.0, linear velocity 40 cm/s, constant flow

MS: Single Quadrupole, Direct Interface, 220 °C Interface Temperature

Acquisition: SIM scan mode

Scan Parameter: 46-250 amu 6.6 scans/s

SIM parameter: m/z 60.74, 6.6 scans/s

T l : n ni lirnril ri n li r il n

Improved polypropylene resins were prepared as follows.

Virgin PP (2) Virgin PP (1)

Example 1b of Example 1a of

Type of catalyst WO document WO document

2015197434 A1 2015197434 A1**

Donor type D D

TEAL/Ti [mol/mol] 250 250

TEAL/Donor [mol/mol] 10 15

prepolymerization

Temperature [°C] 30 30

Pressure [kPa] 5450 5450

Time of

_residence [h] 0.30 0.30

Loop (Reactor 1)

Temperature [°C] 80 80

Pressure [kPa] 5330 5330

H2/C3 ratio [mol/kmol] 1.8 3.5

Time of

residence ^{[h] 0.5 0.5}

reactor division

_loop [% by weight] 60 60

MFR2 [g/10 min] 10 20

GPR (Reactor 2)

Temperature [°C] 80 80

Pressure [kPa] 2500 2500

H2/C3 ratio [mol/kmol] 55 24

Time of

residence of

polymer

[h] 1.5 1.5

MFR in GPR [g/10 min] 53 20

reactor division

GPR [% by weight] 40 40

Polymer

Tm [°C] 165 165

Total MFR [g/10 min] 20 20

XCS [% by weight] 1.9 2.5

Nucleation 0.43% by weight of

[type] _talc none

Virgin polyethylene ("virgin PE") was also produced in a prepoly/loop/gpr reactor combination using a conventional 4th generation ZN catalyst. The loop density was 970 kg/m3 and the loop split was 60% by weight. Al/Ti ratio: 8.3; Essentially identical polyethylene resins are commercially available.

Three compositions were prepared according to the recipes given in Table 4. All compositions were stabilized with 0.3% by weight Irganox B255FF.

T l 4 R ml inv n iv mr iv

continuation

Virgin PP (1) virgin propylene homopolymer with MFR2 of approximately 20 g/10 min, a flexural modulus (ISO 178) of 1350 MPa, a heat deflection temperature B (0.45 MPa; ISO 75-2) of 80 °C and a tensile strength (50 mm/min; ISO 527-2) of 35 MPa

CMB black carbon black masterbatch using virgin PP

Virgin PE virgin high-density polyethylene with a density of 954 kg/m3 (ISO11833), a melt flow rate of 4 g/10 min (ISO 1133; 2.16 kg) and a tensile modulus of 850 MPa (1 mm/ min; ISO 527-2)

AO Irganox B255 FF (amount of 0.3% by weight for all examples)

Ratio iPP/PE+PE-CoPo ratio of iPP vs. polyethylene and ethylene-containing copolymers as described in the methods section

It can be seen that the gloss of the polypropylene-rich recycle was improved by the addition of the virgin propylene homopolymer in an amount of 73% by weight, very close to the value of the virgin material. However, at a low amount of 23% by weight of the virgin propylene homopolymer, the gloss was somewhat lower. The gloss could be further improved by the addition of virgin high-density polyethylene in an amount of 10% by weight:

In the same way, more polyethylene-based recyclates (recycled from lower quality polypropylene/polyethylene/ethylene copolymers) were upgraded. All compositions were stabilized with 0.3% by weight Irganox B255FF.

Recycled lower grade polypropylene/polyethylene/ethylene copolymers

iPP/(PE+PE-CoPo) ratio of approximately 1:1

Table 5 Recipes of eem the inventive com aratives

Virgin PP (2) virgin propylene homopolymer with MFR2 of approximately 20 g/10 min, a flexural modulus (ISO 178) of 2000 MPa, a heat deflection temperature B (0.45 MPa; ISO 75-2) of 115 °C and a tensile strength (50 mm/min; ISO 527-2) of 40 MPa, nucleated by 0.43% by weight of talc (see above)

CMB black carbon black masterbatch using virgin PP (2)

Ratio iPP/PE+PE-CoPo ratio of iPP vs. polyethylene and ethylene-containing copolymers as described in the methods section

It can be seen that the gloss of the lower grade polypropylene/polyethylene/ethylene copolymer recycle could be increased at surprisingly high amounts of the recycle by adding virgin polypropylene homopolymer in a fairly moderate amount.

Claims (11)

1. A polypropylene composition (C) that can be obtained by combining: a) from 20.0 to 80.0% by weight, based on the total weight of the composition, of a combination (A) comprising A-1) isotactic polypropylene A-2) polyethylene as well as ethylene-containing copolymers wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:7, Y wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste; b) from 20.0 to 80.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having (i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min (ii) a flexural modulus (ISO 178) of at least 1200 MPa c) from 0.0 to 15.0% by weight of a virgin high-density polyethylene having (i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 2 to 8 g/10 min (ii) a density of 950 to 960 kg/m3 (ISO 1183), d) 0.0 to 5.0% by weight of a masterbatch of polypropylene and carbon black e) from 0.0 to 3.0% by weight of additives selected from the group of antioxidants and UV stabilizers such that components a) to e) add up to 100% by weight. The polypropylene composition (C) according to claim 1 obtainable by combining: a) 20.0 to 50.0% by weight, based on the total weight of the composition, of a combination (A) comprising A-1) isotactic polypropylene A-2) polyethylene as well as ethylene-containing copolymers wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:2, and wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste; a) from 50.0 to 80.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having (i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min (ii) a flexural modulus (ISO 178) of at least 1200 MPa b) from 0.0 to 15.0% by weight of a virgin high-density polyethylene having (i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 2 to 8 g/10 min (ii) a density of 950 to 960 kg/m3 (ISO 1183), c) from 0.0 to 5.0% by weight of a masterbatch of polypropylene and carbon black d) 0.0 to 3.0% by weight of additives selected from the group of antioxidants and UV stabilizers such that components a) to d) add up to 100% by weight. The polypropylene composition (C) according to claim 2, where the virgin high-density polyethylene has: (iii) a tensile modulus (1 mm/min; ISO 527-2) of at least 800 MPa, optionally up to 1300 MPa. The polypropylene composition (C) according to claims 2 or 3, wherein high-density virgin polyethylene has (iv) a heat deflection temperature (0.45 MPa; ISO 75-2) of at least 62°C and optionally up to 100°C. 5. The polypropylene composition (C) according to any of claims 2 to 4, wherein the polyethylene high density virgin has (v) a Shore D hardness of 56 to 64 (ISO 868), preferably 58 to 64. The polypropylene composition (C) according to claim 1 obtainable by combining: a) from 50.0 to 80.0% by weight, based on the total weight of the composition, of a combination (A) comprising A-1) isotactic polypropylene A-2) polyethylene as well as ethylene-containing copolymers wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 3:2 to 2:3, Y wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste; b) from 20.0 to 50.0% by weight, based on the total weight of the composition, of a virgin polypropylene homopolymer having (i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min (ii) a flexural modulus (ISO 178) of at least 1200 MPa c) from 0.0 to 5.0% by weight of a masterbatch of polypropylene and carbon black d) from 0.0 to 3.0% by weight of additives selected from the group of antioxidants and/or UV stabilizers so that components a) to d) add up to 100% by weight. 7. The polypropylene composition (C) according to any of the preceding claims, wherein the virgin polypropylene homopolymer has: (vi) a tensile strength of 30 to 45 MPa (ISO 527-2); I (vii) a heat deflection temperature B (0.45 MPa; ISO 75-2) of at least 76°C, preferably up to 120°C. 8. A polypropylene composition (C) according to any of the preceding claims, wherein blend (A) has a limonene content determined using solid phase microextraction (HS-SPME-GC-MS) of i) from 1 ppm to 100 ppm, preferably from 1 ppm to 50 ppm, more preferably from 2 ppm to 50 ppm, most preferably from 3 ppm to 35 ppm; either ii) from 0.10 ppm to less than 1 ppm, preferably from 0.10 ppm to less than 0.85 ppm, most preferably from 0.10 ppm to less than 0.60 ppm. 9. A polypropylene composition (C) according to any of the preceding claims, wherein the blend (A) contains one or more of the following components: polystyrene, polyamide, paper, wood and/or polyester in amounts less than 1% by weight. 10. Use of a virgin polypropylene homopolymer together with a virgin high-density polyethylene in a composition comprising a combination (A), such that the combination (A) comprises A-1) isotactic polypropylene A-2) polyethylene as well as ethylene-containing copolymers wherein the weight ratio of isotactic polypropylene (A-1) and polyethylene and ethylene-containing copolymers (A-2) is from 19:1 to 3:2, and wherein the combination (A) is a recycled material, which is recovered from a residual plastic material derived from post-consumer and/or post-industrial waste; such that combination (A) is present in an amount of 20.0 to 35.0% by weight, based on the total weight of the composition; so that said virgin polypropylene homopolymer has (i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 12 to 27 g/10 min (ii) a flexural modulus (ISO 178) of at least 1200 MPa and is present in an amount of 50.0 to 75.0% by weight, based on the total weight of the composition, and so that said high density virgin polyethylene has (i) MFR (230 °C, 2.16 kg; ISO 1133) in the range of 2 to 8 g/10 min (ii) a density of 950 to 960 kg/m3 (ISO 1183). and is present in an amount of 5 to 15% by weight, based on the total weight of the composition, to increase the gloss (gloss measured according to DIN 67530 at an angle of 60°) by at least 2% of the value measurement compared to the gloss of the composition that does not contain the virgin polypropylene homopolymer and that does not contain the virgin high-density polyethylene, so that a masterbatch of polypropylene and carbon black may optionally be present in an amount of 0 to 5.0% by weight with respect to the total weight of the composition. 11. Use according to claim 10, wherein pool (A) has a limonene content determined using solid phase microextraction (HS-SPME-GC-MS) of i) from 1 ppm to 100 ppm, preferably from 1 ppm to 50 ppm, more preferably from 2 ppm to 50 ppm, most preferably from 3 ppm to 35 ppm; either ii) from 0.10 ppm to less than 1 ppm, preferably from 0.10 ppm to less than 0.85 ppm, most preferably from 0.10 ppm to less than 0.60 ppm.